The present invention relates to an emulsion fuel oil, and more particularly to a water-in-oil (W/O) type of emulsion fuel oil. The present invention also relates to a method for forming a water-in-oil (W/O) type of emulsion fuel oil.
The caloric value of combustion of fuel oil (heavy oil) can be converted to mechanical energy or electric energy, and is generally used in boilers or engines. Many countries have set standards and regulations to control the maximal permissible discharge level of pollutants to protect the environment. Thus, reducing the emitted concentration and amount of pollutants, such as sulfur oxide (SOx), nitrogen oxide (NOx) and carbon oxide (COx) as a result of fossil fuel combustion, is an important subject in environmental protection today.
To overcome the problems described above, some methods were developed to form an emulsion fuel oil by mixing a fuel oil, a water and a specific additive, which reduce the employed quantity of fuel oil so as to dilute the emitted concentration of pollutants.
However, the emulsion fuel oil formed with the additive described in the prior arts has disadvantages of:
1. Instability after long time storage: The resulting emulsion fuel oil is not so stable that the water and the oil are readily separated from each other. Most of the emulsion fuel oil can only maintain its emulsifying stability for a few days at room temperature. Thus, the emulsion fuel oil is usually used immediately as it is formed, and is unfavorable for large-scale production and long-distance transportation.
2. Difficult combustion ignition: It is found that such emulsion fuel oil is not easily ignited, and the caloric value of combustion goes down with increased quantity of water (for example, when the added quantity of water is 20 weight percent, the caloric value of combustion will go down to 70% as that of the same volume of fuel oil.) In addition, the emulsion fuel oil cannot be ignited easily when the added quantity of water is above 30 weight percent, which limits its industrial applicability.
It is an object of the present invention to provide an emulsion fuel oil having a caloric value of combustion comparable to that of the same volume of fuel oil.
It is another object of the present invention to provide an emulsion fuel oil having lower emitted concentration and amount of pollutants generated from combustion than that of the same volume of fuel oil.
It is an additional object of the present invention to provide an emulsion fuel oil which can be stored for a long period of time without separation of the fuel oil and the water.
It is an additional object of the present invention to provide a method for forming an emulsion fuel oil.
In accordance with an aspect of the present invention, the emulsion fuel oil includes 550-800 parts by weight of a fuel oil, 200-450 parts by weight of a water, and 2-20 parts by weight of an additive including a non-ionic surfactant having an HLB (Hydrophilic-Lipophilic Balance) value ranged from 2.5 to 8, a combustion-assisting reagent, a stabilization reagent and a promotion reagent.
Preferably, the combustion-assisting reagent is a blend of an organic peroxide, an organic solvent and a diluting oil.
Preferably, the stabilization reagent is made by condensation of a phenol compound and a polyol compound.
Preferably, the stabilization reagent is used for forming a stable interface membrane between the fuel oil and the water at 70-95xc2x0 C.
Preferably, the promotion reagent is an inorganic peroxide.
Preferably, the emulsion fuel oil further includes an antioxidant reagent being one selected from a group consisting of 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-phenol and 2,6-di-tert-butyl-xcex1-dimethylamino-p-cresol.
Preferably, based on 100 parts by weight of the non-ionic surfactant, the combustion-assisting reagent is 5-60 parts by weight, the stabilization reagent is 1-65 parts by weight, the promotion reagent is 0.1-30 parts by weight, and the antioxidant reagent is 1-30 parts by weight.
In accordance with another aspect of the present invention, the method for forming an emulsion fuel oil includes steps of (a) providing a mixture including 550-800 parts by weight of a fuel oil, 200-450 parts by weight of a water and 2-20 parts by weight of an additive, wherein the additive includes a non-ionic surfactant having an HLB (Hydrophilic-Lipophilic Balance) value ranged from 2.5 to 8, a combustion-assisting reagent, a stabilization reagent and a promotion reagent, (b) stirring the mixture by a shearing speed of 2-50 m/s at 70-95xc2x0 C. for 3-20 minutes, (c) rapidly stirring and cutting the mixture by a shearing speed of 10-500 m/s for 6-60 minutes, and (d) continuously stirring the mixture by a shearing speed of 0.5-30 m/s for 5-60 minutes to be cooled down to 45xc2x0 C. for storage.
Preferably, the step (c) produces particles having diameters ranged from 0.3 to 10 xcexcm, and the particles with diameters smaller than 1.5 xcexcm occupy 50-90% of the particles.
Preferably, the step (c) is performed by a stirring device having gear-type blades for cutting the mixture.
Preferably, the combustion-assisting reagent is a blend of an organic peroxide, an organic solvent and a diluting oil.
Preferably, the stabilization reagent is made by condensation of a phenol compound and a polyol compound.
Preferably, the stabilization reagent is used for forming a stable interface membrane between the fuel oil and the water at 70-95xc2x0 C.
Preferably, the promotion reagent is an inorganic peroxide.
Preferably, the additive further includes an antioxidant reagent being one selected from a group consisting of 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-phenol and 2,6-di-tert-butyl-xcex1-dimethylamino-p-cresol.
Preferably, based on 100 parts by weight of the non-ionic surfactant, the combustion-assisting reagent is 5-60 parts by weight, the stabilization reagent is 1-65 parts by weight, the promotion reagent is 0.1-30 parts by weight, and the antioxidant reagent is 1-30 parts by weight.
The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which: